De Moor V:26: Defense of the Deity of the Holy Spirit, Part 2
2. From Attributes, Eternity, Genesis 1:2. They take exception that the Pre-existence of the Spirit before the created mass is not proven from this passage, nor His Eternity by consequence,; since the Water over which He was brooding, and the Earth, rude and disordered, were both existing at that time, equally with the Spirit. I Respond by denying the Consequent; while Water and Earth were existing by the Creation mentioned in verse 1, the Spirit was already existing, yet is not said to have been created in the beginning.
Immensity, Psalm 139:7, where the Essential presence of the Spirit is treated, as it was seen in Chapter IV, § 27. And, when here, and equally also in Genesis 1:2, the Spirit of God is mentioned by way of distinction from God, the name Spirit lead us, not to the divine Essence in general, but to the Third Person in particular, which is distinguished from God, not οὐσιωδῶς/essentially but ὑποστατικῶς/hypostatically/ personally so called, since the Spirit Himself is also a partaker of the divine οὐσίας/being and φύσεως/nature; the Spirit of God and at the same time God the Spirit: as a son of man is himself also a man compare WESSELIUS’ Dissertationes Leidenses IX, § 23, page 331. Now, from this passage, as Bellarmine instructs, book III de Christo, chapter XI, Controversiarum, tome I, column 488, the Fathers prove the Divinity of the Holy Spirit: AMBROSE, book I de Spiritu Sancto, chapter VII; JEROME and CASSIODORUS on Psalm 139; BASIL, de Spiritu Sancto, chapter XXII; CYRIL, book VII de Trinitate; DIDYMUS,book I de Spiritu Sancto; AUGUSTINE book III contra Maximianum; FULGENTIUS, de Fide ad Donatum, chapter VIII. To this same purpose is also cited 1 Corinthians 6:19, because the Spirit is in believers, not only efficaciously, but also by Essence; since He is in them, as God in His temple: compare WITTICH’S Causam Spiritus Sancti, § XI, pages 22-24.
Omniscience, 1 Corinthians 2:10, 11, in which Paul wishes to prove that the Spirit of God best knows, and hence is able infallibly to reveal, what things the eye has not seen, nor the ear heard, etc.: and this he does by this argument, τὸ Πνεῦμα πάντα ἐρευνᾷ, καὶ τὰ βάθη τοῦ Θεοῦ, the Spirit search all things, even the deep things of God. But there is to be no thought here of the searching of one questioning and doubting, but of the searching of one penetrating, and hence intimately knowing, all things, so that this sentence might aptly serve Paul’s scope/goal. Indeed, the verb ἐρευνᾶν, to search, is transferred from the human to the divine, as also happens with other terms; in which case from terms of this sort all imperfections ought to be removed, and that which is noted as perfect by them is to be considered to obtain in an infinitely more perfect manner in God: for, just as by a diligent Searching of a matter we are wont to arrive at a most accurate knowledge of the same, so by a metonymy of the antecedent in the place of the consequent Searching in God speaks of His altogether perfect and intimate Knowledge of a thing. Just as God is often said to search, to prove, or to try men, and their hearts and reins, by the Hebrew verbs בָּחַן, to examine,בִּקֵּשׁ, to seek, דָּרַשׁ, to search,חָקַר, to search. Hence the Spirit is able to teach believers all things, John 14:26, and to predict things future and arcane, Acts 20:23; 1 Timothy 4:1. JEROME, or whoever it was, on 1 Corinthians 2:10, 11, opera Hieronymi, tome 9, page 302: “This is very clear against the heretics that say that the Holy Spirit is a creature. Whence it is here shown that not only is He not a creature, but also that He alone searches God’s inner and deep things: so that He might indeed be of the same nature and substance with Christ.” Ineptly, 1. do the Socinians on the prior part of 1 Corinthians 2:10 understand by τὸ Πνεῦμα τοῦ Θεοῦ, the Spirit of God, the Gospel; see the Catechesin Racovianam, chapter VI, de Prophetico Christi munere, question 8, pages 209, 210, compared with ARNOLDI’S refutatione, § I-VIII, pages 448-450. 2. Not with any more success do they appeal to 1 Corinthians 2, the latter part of verse 10 and verse 11, from the comparison of the Spirit of God with the Spirit of man, that the Holy Spirit is something in God, which is in God by nature, yet not a divine Person, distinct from God the Father, Catechesi Racoviana, chapter VI, de Prophetico Christi munere, question 12, pages 213, 214. For, ARNOLDI resolves this difficulty most satisfactorily, in his refutatione Catecheseos Racovianæ, on the passage cited, § XVI, XVII, page 459, responding, “That similitude of the Spirit, which is in man, is only able to be accommodated to that to which it is accommodated by Paul; namely, to knowledge, and to essential in-being, not further. For, the Spirit of man, since it is part of man, is not able to be a person: but the Spirit of God, which is in God, is not able to be called a part of God; because there are no parts in God. By the same labor a response is here fashioned to that argument of the Socianians: The Spirit of someone is not a person distinct from him whose it is: But the Holy Spirit, etc. Therefore. Of course, the Major applies only in the case of men. For the Spirit of man is not the person of man. But the situation is otherwise in divine things; for the Holy Spirit is not only called the Spirit of the Father, but also of the Son, Galatians 4:6; Romans 8:9. But, as it is not possible to be shown in human things, that one Spirit belongs to two persons, but is possible in divine things; so, even if in human things that Spirit which is in someone is not able to be a person distince from him whose it is, yet it is possible in divine things.” On 1 Corinthians 2:10, 11, compare also LAMPE, de Spiritu Sancto, chapter III, § 24, chapter IV, § 12, 13, Dissertationum philologico-theologicarum, volume II, Disputations IV, V, pages 141, 158, 159.
 Didymus the Blind (c. 313-398) was the head of the Catechetical School of Alexandria, and one of Jerome’s teachers. It is said that his commentaries covered almost the entirety of Scripture, but his work survives only in fragments.  For example, Psalm 26:2: “Examine me (בְּחָנֵנִי), O Lord, and prove me; try my reins and my heart.”  For example, 1 Chronicles 28:9: “And thou, Solomon my son, know thou the God of thy father, and serve him with a perfect heart and with a willing mind: for the Lord searcheth (דּוֹרֵשׁ) all hearts, and understandeth all the imaginations of the thoughts: if thou seek him, he will be found of thee; but if thou forsake him, he will cast thee off for ever.”  For example, Psalm 139:1: “O Lord, thou hast searched me (חֲקַרְתַּנִי), and known me.”